1,4-dihydropyridine compounds useful as reverse resistance agents

A 1,4-dihydropyridine derivative of Formula 1 or a pharmaceutically acceptable salt thereof:

• ##STR74## wherein each of R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 independently represents a hydrogen atom, a lower alkyl group having 1 to 3 carbon atoms, a hydroxy group, a lower alkyloxy group having 1 to 3 carbon atoms, or a nitro group, or two of the substituents represented by R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 adjacent to each other on the benzene ring are combined together to form an alkylenedioxy group having 1 to 3 carbon atoms;
• at least one of R.sup.6 and R.sup.7 represents:
• (i) an alkyloxycarbonyl group selected from the group consisting of a pyridylalkyloxycarbonyl group which may be substituted on the pyridyl moiety, a N,N-dialkylaminoalkyloxycarbonyl group in which the dialkylamino moiety may take on a cyclic structure, a N,N-alkylarylaminoalkyloxycarbonyl group, a N,N-diaralkylaminoalkyloxycarbonyl group, and a N,N-aralkylalkylamino-alkyloxycarbonyl group;
• or
• (ii) an alkylaminocarbonyl group selected from the group consisting of a pyridylalkylaminocarbonyl group which may be substituted on the pyridyl moiety, a (N,N-dialkylamino)alkylaminocarbonyl group in which the dialkylamino moiety may take on a cyclic structure, a (N,N-alkylarylamino)alkylaminocarbonyl group, a (N,N-diaralkylamino)alkylaminocarbonyl group, and a (N,N-aralkylalakylamino)alkyl-aminocarbonyl group;
• and where when only only one of R.sup.6 and R.sup.7 represents said alkyloxycarbonyl group or said alkylaminocarbonyl group, the other is an unsubstituted alkyloxycarbonyl group;
• each of R.sup.8 and R.sup.9 independently represents a hydrogen atom or a lower alkyl group having 1 to 5 carbon atoms;
• n represents an integer of 2 to 9;
• X represents a methylene group or oxygen atom, wherein the methylene is optionally substituted with a lower alkyl group having 1 to 5 carbon atoms, or a lower alkyloxy group having 1 to 5 carbon atoms;
• and,
• R.sup.10 represents an aryl group or an aralkyl group, wherein the aryl moiety in the aryl group and aralkyl group is phenyl or naphthyl at said aryl moiety and is optionally substituted with a substituent selected from the group consisting of a halogen atom, a lower alkyl group having 1 to 5 carbon atoms, a lower alkyloxy group having 1 to 5 carbon atoms, a hydroxy group an aryl group, an aryloxy group, an aralkyl group, or an aralkyloxy group, or two substituents adjacent to each other on the benzene ring are combined together to form an alkylenedioxy group having 1 to 3 carbon atoms.